This invention relates to a filter kit assembly for use, for example, with a panel mount BNC type connector, for filtering the shield of a cable connected to the housing of the connector through a filter, for example, a capacitor, to the panel upon which the connector is mounted, and therefrom to ground.
BNC connectors and coaxial cables are typically employed in applications wherein it is desirable to filter and shield transmissions through conductors connected thereto from outside electromagnetic interference, i.e., EMI, or vice versa. Filtering and shielding are methods of controlling EMI. They may be used independently or together. In this context, for example, such connectors are employed in computer applications wherein data transmissions through the cables employed, typically which are coaxial cables of the type having an electromagnetic shield surrounding an inner conductor, must be protected from electromagnetic interference or interference emissions from the computer must be avoided. In the case of computer applications, such BNC type connectors are often mounted on panels which are made of metallic conducting material, and which lead to a ground. It is typical that in this case, it is desirable to prevent emanation of high frequency signals from a shielded coaxial cable into the environment or from the environment into the equipment. Such a connector then is typically mounted on a panel in electrical contact therewith, and as shown in FIG. 1, the prior art typically involved connecting, by means of leads, a capacitor in a series circuit arrangement to the panel from the outside of the connector housing.
Although generally working satisfactorily for the purpose of shielding high frequency signals and routing them to ground through the filter capacitor, such an arrangement was typically complicated and difficult to assemble and was susceptible to disconnection. Also, the inherent inductance of the leads of the capacitor diminishes the effectiveness of conventional filters at high frequency.
In accordance with the invention, such problems are avoided.